llvm/test/CodeGen/X86/zero-call-used-regs-debug-info.mir

# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -run-pass=prologepilog -o - %s | FileCheck %s

# Test that the presence of debug instructions doesn't trigger arbitrary registers that are unused to be zeroed out.

--- |
  ; ModuleID = 'zero-call-used-regs-debug-info.ll'
  source_filename = "zero-call-used-regs-debug-info.c"
  target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
  target triple = "x86_64-unknown-linux-gnu"

  @b = dso_local local_unnamed_addr global i32 0, align 4, !dbg !0
  @a = dso_local local_unnamed_addr global [1 x i8] zeroinitializer, align 1, !dbg !5

  ; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(readwrite, argmem: none, inaccessiblemem: none) uwtable
  define dso_local signext i8 @c(i32 noundef %d) local_unnamed_addr #0 !dbg !19 {
  entry:
    call void @llvm.dbg.value(metadata i32 %d, metadata !23, metadata !DIExpression()), !dbg !26
    call void @llvm.dbg.value(metadata i32 %d, metadata !24, metadata !DIExpression()), !dbg !27
    %0 = load i32, ptr @b, align 4, !dbg !28, !tbaa !29
    %conv = trunc i32 %0 to i8, !dbg !33
    store i8 %conv, ptr @a, align 1, !dbg !34, !tbaa !35
    ret i8 undef, !dbg !36
  }

  ; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
  declare void @llvm.dbg.value(metadata, metadata, metadata) #2

  attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(readwrite, argmem: none, inaccessiblemem: none) uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" "zero-call-used-regs"="used" }
  attributes #1 = { mustprogress nofree norecurse nosync nounwind willreturn memory(none) uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
  attributes #2 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }

  !llvm.dbg.cu = !{!2}
  !llvm.module.flags = !{!12, !13, !14, !15, !16, !17}
  !llvm.ident = !{!18}

  !0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
  !1 = distinct !DIGlobalVariable(name: "b", scope: !2, file: !3, line: 2, type: !11, isLocal: false, isDefinition: true)
  !2 = distinct !DICompileUnit(language: DW_LANG_C11, file: !3, producer: "clang version 16.0.0 (https://github.com/llvm/llvm-project.git ba5acedd979aa94a81be555e0add8e4421499d4f)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, globals: !4, splitDebugInlining: false, nameTableKind: None)
  !3 = !DIFile(filename: "zero-call-used-regs-debug-info.c", directory: "/home/xgupta/compiler/llvm-project/build/bin", checksumkind: CSK_MD5, checksum: "fe3a5f45289411a008e07c7debb490ca")
  !4 = !{!5, !0}
  !5 = !DIGlobalVariableExpression(var: !6, expr: !DIExpression())
  !6 = distinct !DIGlobalVariable(name: "a", scope: !2, file: !3, line: 1, type: !7, isLocal: false, isDefinition: true)
  !7 = !DICompositeType(tag: DW_TAG_array_type, baseType: !8, size: 8, elements: !9)
  !8 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char)
  !9 = !{!10}
  !10 = !DISubrange(count: 1)
  !11 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
  !12 = !{i32 7, !"Dwarf Version", i32 5}
  !13 = !{i32 2, !"Debug Info Version", i32 3}
  !14 = !{i32 1, !"wchar_size", i32 4}
  !15 = !{i32 8, !"PIC Level", i32 2}
  !16 = !{i32 7, !"PIE Level", i32 2}
  !17 = !{i32 7, !"uwtable", i32 2}
  !18 = !{!"clang version 16.0.0 (https://github.com/llvm/llvm-project.git ba5acedd979aa94a81be555e0add8e4421499d4f)"}
  !19 = distinct !DISubprogram(name: "c", scope: !3, file: !3, line: 3, type: !20, scopeLine: 3, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !2, retainedNodes: !22)
  !20 = !DISubroutineType(types: !21)
  !21 = !{!8, !11}
  !22 = !{!23, !24}
  !23 = !DILocalVariable(name: "d", arg: 1, scope: !19, file: !3, line: 3, type: !11)
  !24 = !DILocalVariable(name: "e", scope: !25, file: !3, line: 5, type: !11)
  !25 = distinct !DILexicalBlock(scope: !19, file: !3, line: 4, column: 9)
  !26 = !DILocation(line: 0, scope: !19)
  !27 = !DILocation(line: 0, scope: !25)
  !28 = !DILocation(line: 6, column: 5, scope: !25)
  !29 = !{!30, !30, i64 0}
  !30 = !{!"int", !31, i64 0}
  !31 = !{!"omnipotent char", !32, i64 0}
  !32 = !{!"Simple C/C++ TBAA"}
  !33 = !DILocation(line: 4, column: 8, scope: !19)
  !34 = !DILocation(line: 4, column: 6, scope: !19)
  !35 = !{!31, !31, i64 0}
  !36 = !DILocation(line: 8, column: 1, scope: !19)
  !37 = distinct !DISubprogram(name: "main", scope: !3, file: !3, line: 9, type: !38, scopeLine: 9, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !2, retainedNodes: !40)
  !38 = !DISubroutineType(types: !39)
  !39 = !{null}
  !40 = !{}
  !41 = !DILocation(line: 9, column: 14, scope: !37)

...
---
name:            c
alignment:       16
exposesReturnsTwice: false
legalized:       false
regBankSelected: false
selected:        false
failedISel:      false
tracksRegLiveness: true
hasWinCFI:       false
callsEHReturn:   false
callsUnwindInit: false
hasEHCatchret:   false
hasEHScopes:     false
hasEHFunclets:   false
debugInstrRef:   true
failsVerification: false
tracksDebugUserValues: true
registers:       []
liveins:         []
frameInfo:
  isFrameAddressTaken: false
  isReturnAddressTaken: false
  hasStackMap:     false
  hasPatchPoint:   false
  stackSize:       0
  offsetAdjustment: 0
  maxAlignment:    1
  adjustsStack:    false
  hasCalls:        false
  stackProtector:  ''
  functionContext: ''
  maxCallFrameSize: 4294967295
  cvBytesOfCalleeSavedRegisters: 0
  hasOpaqueSPAdjustment: false
  hasVAStart:      false
  hasMustTailInVarArgFunc: false
  hasTailCall:     false
  localFrameSize:  0
  savePoint:       ''
  restorePoint:    ''
fixedStack:      []
stack:           []
callSites:       []
debugValueSubstitutions: []
constants:       []
machineFunctionInfo: {}
body:             |
  bb.0.entry:
    ; CHECK-LABEL: name: c
    ; CHECK: DBG_VALUE $edi, $noreg, !23, !DIExpression(), debug-location !26
    ; CHECK-NEXT: DBG_VALUE $edi, $noreg, !24, !DIExpression(), debug-location !27
    ; CHECK-NEXT: renamable $al = MOV8rm $rip, 1, $noreg, @b, $noreg, debug-location !28 :: (dereferenceable load (s8) from @b, align 4, !tbaa !29)
    ; CHECK-NEXT: MOV8mr $rip, 1, $noreg, @a, $noreg, killed renamable $al, debug-location !34 :: (store (s8) into @a, !tbaa !35)
    ; CHECK-NEXT: RET 0, undef $al, debug-location !36
    DBG_VALUE $edi, $noreg, !23, !DIExpression(), debug-location !26
    DBG_VALUE $edi, $noreg, !24, !DIExpression(), debug-location !27
    renamable $al = MOV8rm $rip, 1, $noreg, @b, $noreg, debug-location !28 :: (dereferenceable load (s8) from @b, align 4, !tbaa !29)
    MOV8mr $rip, 1, $noreg, @a, $noreg, killed renamable $al, debug-location !34 :: (store (s8) into @a, !tbaa !35)
    RET 0, undef $al, debug-location !36

...